Welded metal bellows are used in many applications such as pressure sensors, volume compensators, rod or shaft seals, torque couplings and flexible joints. These metal bellows are typically formed from a plurality of thin metallic ring shaped diaphragms which are welded together. Generally, the welding process has two steps--the welding together of two diaphragms forming a convolution, and the stacking of the resulting convolutions and the welding of same to form a bellows arrangement. The prior art method relative to the first step, i.e., the welding together of two diaphragms, requires the use of a fixturing device to hold the diaphragms in intimate contact and alignment while the surfaces defining the inside diameters of the diaphragms are welded. This approach has inherent disadvantages in that the weld speed is relatively slow, the fixturing device must be custom built for each diaphragm design, the fixturing is costly and requires extensive storage space, tooling changeover time is excessive, and the fixturing is generally fabricated from a soft metal which can be nicked or gouged resulting in substantial rework charges.
Because of the foregoing, it has become desirable to develop apparatus for welding thin metallic diaphragms wherein the resulting fixturing, in addition to being simple and relatively inexpensive, can be used for many sizes of diaphragms, does not require extensive storage space, requires minimal changeover time, and is fabricated from a material that does not easily become nicked or gouged, thus minimizing any tooling rework required.